Is there a Jonah in Space Capsules to ISS? Possible Trouble for Juno. Bob Zimmerman,

Oct 19, 2016, 04:15 AM

Zimmerman 10-18-2016 (Photo: Juno in 453 day Jupiter orbit)) Twitter: @BatchelorShow

Is there a Jonah in Space Capsules to ISS? Possible Trouble for Juno. Bob Zimmerman,

“Antares successfully launches Cygnus October 17, 2016 at 11:26 pm Robert Zimmerman

After two years of redesign, Orbital ATK’s Antares rocket tonight successfully put a Cygnus cargo capsule into orbit. Considering that every single one of the vehicles that fly to ISS (Soyuz, Dragon/Falcon 9, Cygnus/Antares, HTV) has been experiencing some issue that has delayed each of their launches, this success tonight must be a relief to managers and engineers in both Russia and the U.S. Next comes a manned Soyuz launch on Wednesday.

Valve problems detected during Juno’s orbital insert around Jupiter has caused engineers to delay the October 19 engine burn that would have lowered the probe’s orbit around Jupiter. Mission managers for NASA’s Juno mission to Jupiter have decided to postpone the upcoming burn of its main rocket motor originally scheduled for Oct. 19. This burn, called the period reduction maneuver (PRM), was to reduce Juno’s orbital period around Jupiter from 53.4 to 14 days. The decision was made in order to further study the performance of a set of valves that are part of the spacecraft’s fuel pressurization system. The period reduction maneuver was the final scheduled burn of Juno’s main engine. “Telemetry indicates that two helium check valves that play an important role in the firing of the spacecraft’s main engine did not operate as expected during a command sequence that was initiated yesterday,” said Rick Nybakken, Juno project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California. “The valves should have opened in a few seconds, but it took several minutes. We need to better understand this issue before moving forward with a burn of the main engine.” Because of this, they will instead use this next close approach to Jupiter to do pure science, something that they would not have done during the engine burn. Though this is a good example of turning lemons into lemonade, it will not be a good thing if Juno can never reduce its orbit to 14 days. A 53 day orbit will mean that they can only do good research every two months, and will seriously limit what they can learn over the long run.